Stress relaxation curves (A) and the normalized stress relaxation functions (B) for the rabbit sciatic nerves from each group.The stress relaxation curves and normalized stress relaxation functions gradually decreased with time in each group, becoming nearly horizontal at 7,200 seconds. Both of the two above types of curves were logarithmic in each group. Data are expressed as the mean ± SD (10 specimens in each group; one-way analysis of variance and Scheffe's method). The decreased values of stress and the normalized stress relaxation functions at 7,200 seconds were different (P < 0.05) among the groups. PLGA: Polylactic glycolic acid; BMSCs: bone marrow mesenchymal stem cells; ECM: extracellular matrix.

Histomorphology of the rabbit sciatic nerves at 24 weeks after transplantation (hematoxylin-eosin staining, light microscope, × 100).(A) In the normal control group, the sciatic nerves were regularly arranged. (B) In the autologous nerve group, myelination occurred at the distal end, and axons (arrows) were located on one side of the elliptic Schwann cells. (C) In the PLGA conduit + BMSCs + ECM group, the sciatic nerve had completely regenerated with good myelination. The nerve fibers (arrows) were regularly arranged. (D) In the PLGA conduit + BMSCs group, the sciatic nerve was also completely regenerated with good myelination, and the nerve fibers (arrows) were regularly arranged. PLGA: Polylactic glycolic acid; BMSCs: bone marrow mesenchymal stem cells; ECM: extracellular matrix.